It has been the hope of this magazine to give producers of agricultural products an opportunity to study the price records of previous years, so that they may, in so far as possible, sell at the time of the year when prices are the highest. It is much to be doubted whether the average reader of charts like that seen in Fig. 92 would realize that the 100 per cent line must be used as a basis for interpreting the chart. The 100 per cent line has not been made any heavier than the other lines on the sheet. A man who had been at all accustomed to reading charts having zero at the base of the chart would be apt to read Fig. 92 as though the bottom line were the zero from which the curve had been drawn. On such a basis, he might think that the price of eggs in January, 1912, was more than eight times the price in July, 1911. Such a conclusion would, of course, be entirely unwarranted by the actual figures.

CURVE PLOTTING

Where charts for index numbers are made on the 100 per cent basis, it would seem best to have a broad Hne for the 100 per cent line. If there is not room to extend the co-ordinate field down to the zero of the vertical scale, the co-ordinate field may be shown broken off with a wavy line at the base indicating to the reader that the bottom of the chart is not a zero line, and that the chart must be read on the 100 per cent basis.